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SOS Informatique Computer repair in Lyon - Individuals and businesses

A red light on my router : what should I do ?

A red light is not always a serious fault, but it always points to one precise stage of the chain. The trick is knowing which one.

The colour codes vary from one provider to another, but the logic is the same everywhere : each light stands for one link, and the first one that fails blocks all the ones after it.

Understanding the chain

From the outside in : the line reaches the building, a termination box converts it, the router connects to that, and it then broadcasts Wi-Fi and feeds the phone and the television. A red Wi-Fi light while the Internet light is green is nothing like a red Internet light - in the first case your access is working, in the second it is not.

What the main lights mean

  • Power red or unlit: the power supply, the socket or the router itself. Try another socket, without a power strip.
  • Fibre or line red: the router is not receiving the provider's signal. Check that the optical cable is pushed fully home at both ends, and above all that it is not bent - an optical fibre pinched behind a piece of furniture is enough to cut the signal, with no visible mark.
  • Internet red while the line light is green: the physical link exists but authentication is failing. Often temporary, often cured by a restart.
  • Wi-Fi red or unlit: wireless broadcasting is switched off. Many routers have a Wi-Fi button on the front, pressed by accident, or a scheduled period when it turns itself off.
  • Phone red: no effect on the internet, the phone line is simply inactive.

Restarting, properly

Unplug the router and the termination box if it is a separate unit. Wait a full minute, plug the termination box back in first, let it synchronise, then the router. A full return takes several minutes on fibre : do not draw conclusions too quickly.

Avoid the factory reset button. It wipes the network name, the Wi-Fi key and all your settings, and you then have to reconnect every device in the house.

Before calling your provider

Check their app or your account area : local outages are reported there, sometimes with an expected restoration time. That saves waiting on the phone for nothing. Note the exact colour too, which light it is, and whether it is steady or flashing - it is the first thing you will be asked.

What is not yours to touch

The optical cable between the street and your home, the connection point in the building and the wall socket belong to the provider. Do not try to clean or reconnect an optical fibre whose tip is exposed : dust and scratches are fatal to it, and the work belongs to a technician.

A house move, building work or a job at a neighbour's are frequent causes of an accidental disconnection at the shared distribution point.

Where we come in

We do not replace your provider on the line itself, but we check everything after the router : internal cabling, configuration, Wi-Fi coverage, devices that will not reconnect. And we help you prepare the call to their technical service with the right details, which often shortens the process.

Frequently asked questions

How long does a router take to restart ?

Reckon on three to ten minutes on fibre, longer after a lengthy outage : the router sometimes picks up an update along the way. Do not unplug it during that phase.

My neighbour has internet and I do not, is that possible ?

Yes. Each home has its own connection at the shared distribution point. A fault can be strictly individual, even within the same building.

Should an old router be replaced ?

If it is more than five years old, exchanging it with your provider often brings better Wi-Fi and better handling of multiple devices. It is generally free.

Further reading

A light that stays red ?

We check everything after the router, and help you with the rest.

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